1. Field of the Invention
The present invention relates generally to drive mechanisms for vehicles having attachments on their back end. In particular, the present invention is a creep lever mechanism for driving an excavating vehicle having a backhoe mounted to the back end, while the operator seat is rotated toward the back of the vehicle to permit control of the backhoe.
2. Description of the Prior Art
Excavating vehicles of the type having a front end loader on their forward end and an attachment such as a backhoe mounted to the rearward end are well known and in widespread use. The operator compartment in these vehicles typically includes a seat which can be rotated from a drive/loader control position facing the front of the vehicle, and a backhoe control position facing the back of the vehicle. Various vehicle drive control mechanisms such as a steering wheel, foot pedal, throttle, clutch, and gear shift lever are mounted in the front of the operator compartment, as is the loader control levers. Backhoe control levers are located at the rear of the operator compartment. The operator drives the vehicle and/or actuates the front end loader when the seat is in the drive/loader control position facing the front of the vehicle. When it is desired to operate the backhoe, the vehicle is stopped and the seat rotated to the rear so the operator can access the backhoe control levers.
Many excavating vehicles of the type described above have a torque converter drive which includes a throttle, clutch, and shift lever. Still other excavating vehicles have a hydrostatic drive. Hydrostatic drives include a hydraulic drive pump which controllably supplies fluid to a hydraulic motor. The hydraulic motor is then coupled to the vehicle's wheels through a drive train. When the operator rotates the foot pedal in a counterclockwise manner, the hydraulic drive pump is stroked in a first direction causing the vehicle to be driven forward. To drive the vehicle in reverse, the operator rotates the foot pedal in a clockwise manner to stroke the hydraulic drive pump in the opposite direction. Vehicle speed in both the forward and reverse directions is determined by the extent of rotation of the foot pedal.
It is often desired to reposition or move the vehicle short distances while operating the backhoe. However, when operating the backhoe, the operator seat will be facing the back of the vehicle. This being the case, the operator does not have access to mechanisms used to drive the vehicle. In vehicles that have a torque converter drive, the operator will sometimes use the backhoe itself to push the machine around. However, operation in this manner is less than desirable. Furthermore, this technique will not work on machines having a hydrostatic drive.
It is evident that there is a continuing need for improved drive control mechanisms in excavating vehicles. Specifically, a mechanism is needed which will permit an operator to drive the vehicle while facing and controlling an attachment mounted to the back of the vehicle. The mechanism should of course be relatively uncomplicated. The mechanism should not interfere with the vehicle's primary drive mechanisms either.